This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Much is known about the mammalian cerebellum, but a clear understanding of the computation performed by its local circuitry and of its role in information processing are still lacking. This project is directed at obtaining insight into cerebellar function in general through a study of the unique cerebellum of mormyrid electric fish. The goals of the project are to establish the major features of functional circuitry, synaptic plasticity and information processing in the mormyrid cerebellum. The primary method will be intracellular recording with staining of recorded elements for morphological identification from an in vitro slice preparation and in vivo whole animal preparation, with pharmacological methods supplemented with immunocytochemistry. The Specific Aims of the project are: (1) To determine the basic functional circuit of the mormyrid cerebellum. (2) To determine the different types of plasticity at parallel fiber and Purkinje cell synapses. (3) To describe information processing in the valvula by examining the effects of electrosensory stimuli, the effects of EOD motor command signals and the interaction between these two types of signals. The findings obtained in the in vitro slice preparation under Specific Aims 1 and 2 will be integrated with the findings obtained in the intact animal under Specific Aim 3 to understand the processing of normal sensory and motor information in the valvula and how that processing is altered by experience. Findings at each level will be compared with the findings in mammalian systems that are obtained in other laboratories to see where the mormyrid studies can provide useful perspectives or insights into mammalian cerebellar function.